Field of the Invention
The present invention relates to pneumatic tires.
Description of the Related Art
A pneumatic tire is mounted on a rim and used. When the tire is mounted on a rim, fastening force is generated mainly with respect to the rim by cores of beads and portions that are inward of the cores in the radial direction. When the tire is mounted on the rim, portions of the tire around the beads and the rim contact with each other to obtain airtightness. The tire mounted on the rim is inflated with air. The tire inflated with air is used.
JP2014-94694 (US2015/0283865) discloses a tire in which cushion layers are disposed in portions that are inward of bead cores in the radial direction. The cushion layers allow reduction in variation of fastening force in the tire mounted on a rim. The tire is excellent in fittability to a rim. JP2010-12829 discloses a tire in which a radius of curvature of bead heels is increased, and an air seal is filled between the bead heels and a rim. The tire is excellent in airtightness.
For a pneumatic tire, both improvement of fittability to a rim and improvement of airtightness are required. The tire disclosed in JP2014-94694 is excellent in fittability to a rim. An air seal is filled between the bead heels of the tire and the rim, whereby airtightness can be improved. However, an air seal is necessary for airtightness. Filling of the air seal causes increase of time and labor for mounting of the tire on a rim.
An object of the present invention is to provide a pneumatic tire that is excellent in both fittability to a rim and airtightness.